Advances with prostheses, e.g. transfemoral prostheses, in recent years have enabled individuals with amputated extremities to pursue a reasonably normal life, and the use of such prostheses is generally well known. Peripheral vascular disease (poor circulation of the blood), cancer, diabetes, accidents, and congenital disorders are the major causes of amputation. Amputations in the case of various diseases are often performed as a lifesaving measure.
The use of transfemoral prostheses by transfemoral amputees is generally well known. In general, transfemoral prostheses include the following four major components: a socket, a knee system, a shank, and a foot-ankle system. A variety of sockets, knee systems, shanks, and foot systems are available, and can be combined to produce a transfemoral prosthesis that best meets the need of each individual transfemoral amputee. The socket is the interface between the amputee and the prosthesis, and it provides the means for transferring the weight of the amputee to the ground by the way of the prosthesis. The knee system provides a transfemoral amputee a normal appearance while walking. The primary purpose of the shank is to transfer the vertical loads caused by the weight of the amputee to the foot system, and subsequently to the ground.
The use of a quadrilateral socket (“quad socket”) for fitting a transfemoral prosthesis to the residual limb (“residuum”) of a transfemoral amputee is generally well known. In general, a quad socket has four walls (quad), and each wall has a specific function. The four walls of a quad socket include an anterior wall, a posterior wall, a medial wall, and a lateral wall.
Several factors should be considered in order to achieve a proper design for a socket including the following: whether the socket satisfactory transmits the load; whether the socket provides satisfactory stability; whether the socket provides efficient control for mobility; whether the socket is easily fitted; and whether the socket is comfortable.
U.S. Pat. No. 4,872,879 discloses an ischial containment socket for securing an artificial limb to the residual thigh of an above-knee amputee. The ischial containment socket includes an interface to which a cup shape frame can be selectively secured, and the interface has open proximal and distal ends. Furthermore, said interface includes a posterior, a medial, a lateral, and an anterior wall. The medial wall includes an extension, which overlaps the anterior wall. The overlapping relation of the extension and the anterior wall forms a peripheral discontinuity, which permits the peripheral dimensions of said interface to be adjusted by sliding the contiguously juxtaposed, and overlapping extension and the anterior wall. The proximal portion of both the posterior and medial walls terminate in a containment brim.
U.S. Pat. No. 4,988,360 discloses a method for fitting the interface portion of an ischial containment socket to the residual limb of above-knee amputee. The interface-fitting module includes a sleeve-like body portion with open proximal and distal ends, and a frame. Said sleeve-like body includes a posterior, a medial, a lateral, and an anterior wall. The lateral wall includes an extension, which overlaps the anterior wall, and the overlapping relation of the extension and the anterior wall forms a peripheral discontinuity, which permits the peripheral dimensions of said interface to be adjusted by sliding the contiguously juxtaposed, and overlapping extension and the anterior wall. The sleeve-like body portion is further provided with a brim.
U.S. Pat. No. 5,653,766 discloses a prosthetic device for use immediately after a limb reduction surgery until the patient is fitted with a more permanent prosthesis. The post prosthetic device includes a sleeve that is at least partially received about a limb. The sleeve includes a first portion and a second portion. The first portion includes a longitudinal slit, which enables the inner surface circumference of the first portion to be adjusted.
Despite the advances in the art, there is still a need for an improved socket, which is easily fitted, and provides a high level of stability and comfort as well as satisfactory load transmission and mobility control.